This invention relates to a section feeder for a book binding machine, namely, an apparatus for feeding gathered sections from a collator to a book production line of a book binding machine.
In a conventional automatic book binding machine, a plurality of clamps are continuously moved on a book production line. Then gathered sections from a collator are clampingly held by the clamps and conveyed on the book production line along which a spine processing unit, a gluing unit and a cover application unit and so forth are arranged.
At the beginning of a book binding process, it is necessary to successively feed the sections from a collator to the book production line so that they are clampingly held by the clamps. Conventionally, because of a structure of the clamp, the section is lifted up from a section supply station below the clamp's travelling path to a section delivery station on the clamp's travelling path, and then the sections are clamped by the clamps having arrived at the section delivery station.
In order to achieve such lifting operation of the sections, it has been proposed to dispose an endless chain between the section supply station and the section delivery station in order to form an inclined path for conveying the sections. In this construction, the sections are conveyed by the chain from the section supply station to the section delivery station. However, while the sections are conveyed by the chain, the position of the sections are suddenly changed due to large bending of the section conveying direction at the time of the sections putting on the chain and at the time of the sections betting down the chain after elevation. Consequently, there is a possibility that the alignment of sections is disturbed. This problem can be solved by diminishing an angle of inclination of the chain, but it is not desirable because of enlargement of apparatus size.
In order to solve this problem, there has been proposed an apparatus for feeding sections gathered by a collator to a book binding machine without tilting the sections during feed operation of the sections (Japanese Patent Publication No. 17725 of 1986). In this apparatus, sections are conveyed by pushing pins, which are guided in an endless loop. from a collator to a section supply station along a horizontal travelling path. Furthermore, a plurality of endless chains are arranged in parallel with one another between the section supply station and the section delivery station. And a plurality of pins for supporting the sections are attached to each of the chains. Then the sections are lifted to the section delivery station by engagement of its spine with the pins without tilting.
However, in such apparatus, it is considerably troublesome to adjust the section lifting mechanism in such a manner that the associated pins of the chains engage with the spine of the section all at once. Especially, such adjustment becomes further difficult because the chains tend to wave during rotation. If the pins of the chains fail to engage with the spine of the section all at once, the section may tilt on the pins and slip down from the pins.
According to this apparatus, the level of the section delivery station cannot be adjusted. But the cut length of the spine is not always constant and it is necessary to adjust the level of the section delivery station by further travelling the section on an alignment plate after lifting the section to the section delivery station. In order to achieve this, there should be provided an additional space (corresponding to at least one clamp) for travel of the section on the alignment plate, which leads to a large-sized book binding machine.